Impact-type mixer



Oct. 27, 1964 w. A. WOOTTEN IMPACT-TYPE MIXER Filed Oct. 22', 1962 .N I W A I INVENTOR. W u/mw ,4. haarrilv M Jaw my United States Patent Ofi ice 3,154,257 Patented Oct. 27, 1964 3,154,257 m iPACT-TYPE MIXER William A. Wootten, Palos Verdes Estates, Calif., assignor to Magnetic Film and Tape Company, Inc, Gardena, Cahi, a corporation of California Filed Oct. 22, 1962, Ser. No. 232,171 Claims. ((11. 241-411) The present invention relates generally to mixing and grinding devices for particulate material and, more particularly, to such devices of the impact type in which the material is subjected to impact blows, with or without grinding between relatively sliding surfaces. tion is particularly adapted to the mixing and grinding of particulate material suspended in a liquid medium.

In mixing finely divided particulate material with liquid carriers, it is desired to break up any groups or clurnps of particles and to distribute them as evenly and finely as possible throughout the carrier liquid. At the same time, it may be desired to further comminute the particulate material to a smaller size during the mixing operation. Devices of this type are used, by way of example only, in the mixing and grinding of finely divided particulate solid material, such as iron oxide and pigments, such as lead oxide, in liquid lacquers, binders and thinners and in aqueous slurries. According to the present invention, the particulate material suspended in the liquid carrier is passed between impacting surfaces by which repeated blows are imparted to the material, and at the same time the engaged surfaces are given a relative sliding movement to grind the particulate material therebetween. In this manner, groups and clumps of particles are broken up into their individual constituents and the particles themselves are reduced to a smaller size.

An object of the present invention is the provision of an improved mixer and grinder for particulate material.

Another object of this invention is the provision of an improved mixing device for breaking up and thoroughly distributing particulate material in a liquid carrier.

A further object of this invention is the provision of an improved mixing and grinding device for particulate material suspended in a carrier liquid in which the material is impacted between surfaces of relatively large area wll ch are also given relative movement to effect a grinding operation.

A still further object of this invention is the provision of an improved mixing and grinding device for particulate material including hammer and anvil elements between which the material is impacted, with the elements being given transverse relative movement to effect a grinding operation therebetween.

These and o her objects and features of this invention will be readily apparent to those skilled in the art from the following specification and the appended drawing illustrating a presently preferred embodiment of the invention, in which:

FIG. 1 is a vertical sectional view through a mixing and grinding device according to the present nvention;

FIG. 2 is a horizontal view, partly in plan and partly broken away, of the impacting and grinding elements of the device;

FIG. 3 is a detailed view illustrating the operation of the mixing and grinding device according to the present invention; and

FIG. 4 is a detailed, horizontal sectional view on the plane 44 of FIG. 1.

In the embodiment of the invention selected for illustration in the drawing, there is provided a central, main body portion 11 having a top plate 12 and a bottom plate 13 mounted thereon, with the three body elements connected together by elongated through-bolts 14. The top plate 12 is sealed to the body portion 11 at 15 and the The inven-.

bottom plate 13 is sealed thereto at 16. A central opening 17 extends vertically through the body portion 11 and communicating therewith are longitudinally and radially extending openings 18. Within the central opening 17 is disposed a rotating anvil 19 having a plurality of flat, longitudinally extending faces 21 thereon, the specific embodiment of the invention selected for illustration in the drawing employing six such faces and being hexagonal in cross section.

The openings 13 conform in number to the number of the faces 21 on the anvil, and disposed in each of the openings 18 is a hammer bar 22 movable both radially and axially of the main body portion 11 of the device. Each hammer bar 22 has a face 23 which cooperates with a face 21 on the central anvil in the impacted position of the device, as shown in FIG. 2. Compression springs 24 are received at one end within sockets 25 in the backs of the bar hammers 22 and engage the back faces 26 of the openings 18 to bias the hammer bars 22 into engagement with the central anvil 19.

The central anvil 19 has an integral upper shaft portion 27 extending therefrom which has a peripheral groove 28 therein within which ride suitable bearing balls 29. The balls 29 are mounted in hemispherical sockets 30 in the side walls of a shaft-receiving socket 31 provided in the top plate 12 and the boss 32 integral therewith. A seal 33 is provided between the bearing balls 29 and the anvil 19.

At its lower face, the arivil 19 has a pair of depending lugs 34 and 35 received within peripheral slots 36 and 37, respectively, in the upper end of a drive shaft 38 driven by any desired means, such as the electric motor 39 diagrammatically shown in FIG. 1. The cooperating depending lugs 34, 35 and slots 36, 37 provide a lostmotion connection between the drive shaft 38 and the central anvil 19 so that the latter will be rotatably driven by the shaft but may rotate forwardly a limited amount independently thereof. A thrust bearing, including hearing balls 41 riding between a seat 42 in the bottom plate 13 and a seat 43 on the shaft 33, supports the shaft and the anvil 19 for rotary motion.

A cam plate 44 is rigidly mounted on the shaft 38 to turn therewith and has an inclined upper surface 45 along which roll balls 46 seated at 47 in the bottom surfaces of the hammer bars 22. A seal between the mixing and grinding portion of the device and the bottom thrust bearing is provided at 48.

An opening 51 through the top plate 12 leads to an annular recess 52 in the bottom face thereof above the junction between the surfaces 21 on the anvil 19 and the surfaces 23 on the hammer bars 22. A pipe 53 threaded or otherwise secured in the opening 51 provides an inlet or outlet for the mixing and grinding device according to the present invention, depending upon which direction the particulate-carrying liquid is to flow through the device. An opening 55 in the bottom plate 13 has communication with the s ace above the cam plate 44 and has a supply or outlet pipe 56 secured therein.

In the operation of the mixing and grinding device according to the present invention, the shaft 38 is rotated, as by the electric motor 39, at relatively slow speed and a liquid having particulate matter in suspension therein is fed into one of the pipes 53, 56 and removed from the other. As the shaft 38 rotates, it rotates the anvil 19 therewith through an arc corresponding to the movement of the anvil from the impacted position of FIG. 2 into the deadcenter position of FIG. 3, where the corners 5! of the anvil are at the center planes of the hammer bars 22. FIG. 4 illustrates the lost-motion connection between the anvil 19 and the shaft 38 provided by the cooperating lugs 34, 35 and 3 slots 36, 37 while driving is being effected. As the anvil 19 rotates from the position of FIG. 2 into the full line position of FIG. 3, the hammer bars 22 are moved back within the openings 18 against the resilient bias of the compression springs 24.

After the corners 59 of the anvil 19 pass the center plane positions of FIG. 3, the biases on the hammer bars 22 are exerted on the anvil 19 to cause continued rotation thereof in the same direction, independently of rotation of the shaft 38 so that the depending lugs 34, 35 move freely to the opposite sides of the slots 36, 37 and the surfaces 23 of the hammer bars 22 engage the surfaces 21 on the anvil 19 with impact blows to crush any clumps or cohering groups of particulate that may be disposed between the surfaces.

As the hammer bars 22 move outwardly and into the openings 18, space is provided inwardly thereof within which the particulate-suspending liquid may flow. As the hammer bars 22 move inwardly again into engagement'with the anvil, this material may be moved toward the outlet of the device or, if the space provided is not filled with the particulate-carrying liquid, it will be moved upwardly to spread out over the cooperating surfaces of the hammer bar and anvil. The dotted line position of FIG. 3 represents an intermediate position during which the anvil 19 is freely rotating under the bias of the springs 24 and the hammer barstare moving into impacting position.

When the anvil 19 is arrested with the surfaces 23 and 21 engaged, it remains stationary while the shaft 38 continues to rotate until the counterclockwise edges of the slots 36 and 37 again engage the depending lugs 34 and 35. The cam plate 44 is being rotated with respect to the hammer bars 22 and the balls 46 so that, with the balls riding up and down the inclined cam surface 45, the hammer bars 22 are given axial, longitudinal movements whereby the surfaces 23 are moved upwardly and downwardly with respect to the cooperating anvil surfaces 21 and thus effect a grinding action to further break up and comminute the particulate material disposed between the cooperating faces 21, 23. Therefore, the particulate and any clumps or groups thereof are subjected to impacts between the anvil 19 and the hammer bars 22 and thereafter are subjected to a grinding action between the relatively sliding surfaces 21 on the anvil and 23 on the hammer bars. To insure maintaining the hammer bars 22 in the lowermost position permitted by the engagement of the balls 46 with the cam surface 45, compression springs 58 may be disposed in sockets 59 in the top faces of the hammer bars and bearing against the under face of the top plate 12 to bias the hammer bars downwardly.

While a certain preferred embodiment of the invention has been specifically illustrated and described, it will be understood that the invention is not limited thereto, as many variations will be apparent to those skilled in the art, and the invention is to be given its broadest interpretation within the terms of the following claims.

I claim:

1. A mixing device comprising: a rotatable anvil having a plurality of impact surfaces thereon; a plurality of hammers having impact surfaces thereon engageable with said anvil impact surfaces; means biasing said harnmers toward said anvil; means for rotating said anvil to move said hammers against their biasing means; and means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias to provide impact between the hammer and anvil surfaces.

2. A mixing device comprising: a rotatable anvil having a plurality of fiat surfaces thereon; a plurality of hammers having fiat surfaces thereon engageable with said anvil surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to move said hammers against their biasing means; means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias; means for feeding particulate material between said anvil and hammer surfaces adjacent to one end of the anvil; and means for removing the particulate material from the opposite end of said anvil.

3. A mixing device for particulate material suspended in a liquid carrier comprising: a rotatable anvil having a plurality of flat impact surfaces thereon; a plurality of hammers having flat impact surfaces thereon engageable with said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to move said hammers against their biasing means; means for feeding carrier liquid and particulate material between said hammer and anvil surfaces while they are separated; and means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias to impact the particulate material between the anvil and hammer surfaces. 7

4. A mixing and grinding device for particulate material suspended in a liquid carrier comprising: a rotatable anvil having a plurality of flat impact surfaces thereon; a plurality of hammers having flat impact surfaces thereon engageable with said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to move said hammers against their biasing means; means for feeding carrier liquid and particulate material between said hammer and anvil surfaces while they are separated; means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias to impact the particulate material between the anvil and hammer surfaces; and means for effecting relative axial movement between said anvil and hammers to grind the particulate between said impact surfaces.

5. A mixing and grinding device for particulate material suspended in a liquid carrier comprising: a rotatable anvil having a plurality of flat impact surfaces thereon; a plurality of hammers having fiat impact surfaces thereon engageable with said anvil impact surfaces; means bias- 7 ing said hammers toward said anvil; means for rotating said anvil to move said hammers against their biasing means; means for feeding carrier liquid and particulate material between said hammer and anvil surfaces while they are separated; means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias to impact the particulate material between the anvil and hammer surfaces; and means providing a cam surface rotatable with said anvil rotating means while the anvil remains stationary after a free forward rotation, for effecting relative axial movement between said anvil and hammer surfaces while they are engaged, to grind the particulate material therebetween.

6. A mixing device for particulate material suspended in a liquid carrier comprising: a rotatable anvil having a plurality of axially extending, flat impact surfaces about its periphery; a plurality of hammers providing axially extending, flat impact surfaces of substantially the same dimensions as said anvil impact surfaces and with said hammers equal in number to said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to engage the surfaces thereon intermediate its impact surfaces with said hammer impact surfaces to move said hammers against theirtbiasing means; means for feeding carrier liquid and particulate material into the spaces between said separated hammer and anvil surfaces; and means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil under the bias of said hammer biasing means after said intermediate anvil surfaces pass the center planes of said hammers, whereby to impact the particulate between the hammer and anvil surfaces under the bias of said hammer biasing means.

7. A mixing and grinding device for particulate material suspended in a liquid carrier comprising: a rotatable anvil having a plurality of axially extending, flat impact surfaces about its periphery; a plurality of hammers providing axially extending, fiat impact surfaces of substantially the same dimensions as said anvil impact surfaces and with said hammers equal in number to said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to engage the surfaces thereon intermediate its impact surfaces with said hammer impact surfaces to move said hammers against their biasing means; means for feeding carrier liquid and particulate material into the spaces between said eparated hammer and anvil surfaces; means providing a lostmotion connection between said anvil and its rotating means to provide for free rotation of said anvil under the bias of said hammer biasing means after said intermediate anvil surfaces pass the center planes of said hammers, whereby to impact the particulate between the hammer and anvil impact surfaces under the bias of said hammer biasing means; and means for effecting relative axial movement between said hammer and anvil impact surfaces when they are engaged, to efiect grinding of the particulate between said surfaces.

8. A mixing and grinding device for particulate material suspended in a liquid carrier comprising: a rotatable anvil having a plurality of axially extending, flat impact surfaces about its periphery; a plurality of hammers having axially extending, fiat impact surfaces of substantially the same dimensions as said anvil impact surfaces and with said hammers equal in number to said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to engage the surfaces thereon intermediate its impact surfaces with said hammer impact surfaces to move said hammers against their biasin means; means for feeding carrier liquid and particulate material into the spaces between said separated hammer and anvil surfaces; means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil under the bias of said hammer biasing means after said intermediate anvil surfaces pass the center planes of said hammers, whereby to impact the particulate between the hammer and anvil impact surfaces under the bias of said hammer biasing means; means for effecting relative axial movement between said hammer and anvil impact surfaces when they are engaged to effect grinding of the particulate between said surfaces, said last-mentioned means including a cam rotatable with said anvil rotating means while the anvil remains stationary after free rotation and moving the hammers axially in one direction; and means biasing said hammers toward the cam.

9. A mixing device for particulate material suspended in a liquid carrier comprising: a main body element providing a central opening and a plurality of guide means extending radially therefrom; a rotatable anvil disposed in said central opening with its axis of rotation transverse to said guide means; a plurality of flat, axially extending impact surfaces about the periphery of said anvil and equal in number to said guide means; a plurality of hammers mounted by said guide means for movement toward and away from the axis of said rotatable anvil, each of said hammers having a flat impact surface thereon of substantially the same dimensions as the impact surfaces on the anvil and engageable successively with said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to engage the surfaces thereon intermediate its impact surfaces with said hammer surfaces to move said hammers back against their biasing means; means for feeding carrier liquid and particulate material into the spaces between the separated hammers and anvil; and means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias as said intermediate anvil surfaces pass the center planes of said hammers, thereby to engage said particulate material between said hammer and anvil impact surfaces.

10. A mixing and grinding device for particulate material suspended in a liquid carrier comprising: a main body element providing a central opening and a plurality of guide means extending radially therefrom; a rotatable anvil disposed in said central opening with its axis of rotation transverse to said guide means; a plurality of flat, axially extending impact surfaces about the periphery of said anvil and equal in number to said guide means; a plurality of hammers mounted by said guide means for movement toward and away from the axis of said rotatable anvil, each of said hammers having a flat impact surface thereon of substantially the same dimensions as the impact surfaces on the anvil and engageable successively with said anvil impact surfaces; means biasing said hammers toward said anvil; means for rotating said anvil to engage the surfaces thereon intermediate its impact surfaces with said hammer surfaces to move said hammers back against their biasing means; means for feeding carrier liquid and particulate material into the spaces between the separated hammers and anvil; means providing a lost-motion connection between said anvil and its rotating means to provide for free rotation of said anvil forwardly of its rotating means under said hammer bias as said intermediate anvil surfaces pass the center planes of said hammers, thereby to engage said particulate material between said hammer and anvil impact surfaces; and means for effecting relative axial movement between said hammer and anvil surfaces while engaged so as to grind the particulate material therebetween.

References Cited in the file of this patent -UNITED STATES PATENTS 719,695 Roberts Feb. 3, 1903 1,451,150 Fraser Apr. 10, 1923 1,693,247 Molz Nov. 27, 1928 

1. A MIXING DEVICE COMPRISING: A ROTATABLE ANVIL HAVING A PLURALITY OF IMPACT SURFACES THEREON; A PLURALITY OF HAMMERS HAVING IMPACT SURFACES THEREON ENGAGEABLE WITH SAID ANVIL IMPACT SURFACES; MEANS BIASING SAID HAMMERS TOWARD SAID ANVIL; MEANS FOR ROTATING SAID ANVIL TO MOVE SAID HAMMERS AGAINST THEIR BIASING MEANS; AND MEANS PROVIDING A LOST-MOTION CONNECTION BETWEEN SAID ANVIL AND ITS ROTATING MEANS TO PROVIDE FOR FREE ROTATION OF SAID ANVIL FORWARDLY OF ITS ROTATING MEANS UNDER SAID HAMMER BIAS TO PROVIDE IMPACT BETWEEN THE HAMMER AND ANVIL SURFACES. 